1. Field of the Invention
The present invention relates to crystallized glass articles having surface patterns imparting to them an appearance of natural stone or stones which are adaptable for use as heat resistant, incombustible ornamental wall materials for buildings and the like, in particular, to such crystallized glass articles having an uneven or non-flat surface.
2. Description of the Prior Art
As substitution of natural marble for ornamental building materials, crystallized glass articles have been proposed which have high mechanical strength, excellent heat resistance and excellent efflorescence resistance. For example, U.S. Pat. Nos. 3,761,235 3,964,917 and 3,955,989, Japanese Patent Publication (JP,B2) No. 60-49145, JPA 63-40736 and others.
Those crystallized glass articles are commonly produced with a flat surface. It is possible by use of a mold having an uneven, rugged or rough pattern in the mold surface to provide an uneven surface pattern to those article. However, an uneven surface pattern is only possible by use of such a mold. For various uneven surface patterns, a large number of molds must be provided, which is uneconomical.